Use Ansible to create and tag Instances in AWS (EC2)

It may be handy to quickly create few instances for testing in AWS.

For such case I'm using simple Ansible playbook which can deploy few CenOS 7 instances, configure disks, tags volumes and instances and install public ssh key to root for example.

AWS Console

IPA (CentOS7) integration with Active Directory (W2K8)

I have been working with IPA in past few months and I would like to share my notes about the IPA and AD integration.

Network diagram:

I created the trust between the Active Directory and IPA server. There is one windows client connected to the AD and one CentOS7 client connected to the IPA. Both clients are "registered" into the AD/IPA.

Loadbalancing of PostgreSQL databases using pgpool-II and repmgr

I have to solve the PostgreSQL HA and Redundancy few weeks ago. It has been written a lot about this topic, but I was not able to find some guide describing pgpool-II and repmgr. After reading some documents I build the solution which I'm going to describe.

In short it contains the Master/Slave DB Streaming replication and pgpool load distribution and HA. The replication "part" is managed by repmgr.

Here is the network diagram:

Update offline CentOS/RHEL server

Sometimes you have a RHEL/CentOS server which is not connected to the Internet. But you should also install security update to prevent local hackers to mess up your system.

I was not able to find some nice description how to do it. Some people are using proxies - but then you still need some connection to the proxy - which can not be the case.

Here is my way how I did it....